CNC Machining worked example
CNC Feed Rate with spindle speed of 20,000 RPM: a worked example
This scenario runs the cnc feed rate calculation on the strong side: spindle speed of 20,000 RPM, with every other input held at its documented default. selecting a starting feed rate for a cutter, comparing CAM defaults with tooling guidance, or documenting feeds and speeds for a setup sheet
The inputs for this scenario
- Spindle speed: 20,000 RPM (raised for this scenario; the documented default is 8,000)
- Flutes or teeth: 3 count (unchanged)
- Chip load: 0 in / tooth (unchanged)
- Feed override: 1 x (unchanged)
Working through the calculation
- Applying the documented formula (Feed rate = spindle speed × flutes or cutting teeth × chip load per tooth × feed override) to the inputs above produces each figure below.
- At this operating point the engine returns 240 in / min for programmed cnc feed rate, the number this scenario is built around.
- At this operating point the engine returns 240 value for base product.
- At this operating point the engine returns 1 x for multiplier.
- At this operating point the engine returns 60,000 value for factor a x b.
How this compares with the baseline
- Against the tool's baseline example, where spindle speed sits at 8,000 RPM and the headline result is 96 in / min, this scenario comes in 150% above the baseline at 240 in / min.
- Use it when setting up a new tool, switching materials, or dialing in a roughing or finishing pass and you need the IPM value to enter into the controller or CAM post. Treat this as a target state: the delta against the baseline quantifies what the improvement is worth before you commit to chasing it.
Results at a glance
- programmed CNC feed rate: 240 in / min (headline result)
- Base product: 240 value
- Multiplier: 1 x
- Factor A x B: 60,000 value
Run it with your numbers
- Every input above is editable in the live CNC Feed Rate calculator, which recalculates instantly and can be shared with the inputs intact.
Last reviewed 2026-05-12.